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From Jeremy Dunck <jdu...@gmail.com>
Subject Re: Ring management and load balance
Date Thu, 25 Mar 2010 16:40:32 GMT
On Thu, Mar 25, 2010 at 10:56 AM, Jonathan Ellis <jbellis@gmail.com> wrote:
> The advantage to doing it the way Cassandra does is that you can keep
> keys sorted with OrderPreservingPartitioner for range scans.  grabbing
> one token of many from each node in the ring would prohibit that.
>
> So we rely on active load balancing to get to a "good enough" balance,
> say within 50%.  It doesn't need to be perfect.

Isn't this also only a real resource was with small clusters?  As you
add nodes, they all get smoothed out (by halving the hottest node),
and if you have a 50-node cluster, 1/50 to 1/100 is a relatively small
difference.

You certainly wouldn't want to shuffle all the data when adding a node
for perfect balance...

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